<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 3//EN">
<HTML><HEAD>
<TITLE>IBM Visualization Data Explorer Programmer&#39;s Reference</TITLE>

<META HTTP-EQUIV="abstract" CONTENT="IBM Visualization Data Explorer
Programmer&#39;s Reference">
<META HTTP-EQUIV="contact" CONTENT="IBM Visualization Data Explorer
(ibmdx@watson.ibm.com)">
<META HTTP-EQUIV="owner" CONTENT="IBM Visualization Data Explorer
(ibmdx@watson.ibm.com)">
<META HTTP-EQUIV="updated" CONTENT="Tue, 16 Sep 1997 ">
<META HTTP-EQUIV="review" CONTENT="Fri, 14 Aug 1998 ">

<META HTTP-EQUIV="keywords" CONTENT="GRAPHICS VISUALIZATION VISUAL PROGRAM DATA
MINING">
<meta http-equiv="content-type" content="text/html;charset=ISO-8859-1">
</HEAD><BODY BGCOLOR="#FFFFFF">

<A NAME="Top_Of_Page"></A>
<H1>IBM Visualization Data Explorer Programmer&#39;s Reference</H1>
<B>&#91; <A HREF="#Bot_Of_Page">Bottom of Page</A> &#124; <A
HREF="progu038.htm">Previous Page</A> &#124; <A HREF="progu040.htm">Next
Page</A> &#124; <A HREF="../proguide.htm#ToC">Table of Contents</A> &#124; <A
HREF="progu037.htm#PToC13">Partial Table of Contents</A> &#124; <A
HREF="progu344.htm#HDRINDEX_START">Index</A> &#93;</B><HR><P>
<HR>
<H2><A NAME="HDRMODSIOR" HREF="progu037.htm#PToC_78">11.3 Inboard, Outboard, and
Runtime-loadable Modules</A></H2>
<A NAME="IDX329"></A>
<A NAME="IDX330"></A>
<A NAME="IDX331"></A>
<P>
The chief differences between inboard, outboard, and runtime-loadable
modules lies in the following features:
<UL COMPACT>
<LI>the module description file (<TT><STRONG>&#46;mdf</STRONG></TT>)
<LI>the compilation and linking process (i.e., the Makefile)
<LI>the command that starts Data Explorer using the module.
</UL>
<P>
Module description files are discussed in <A HREF="progu037.htm#HDRMDFSEC">11.1
, "Module Description Files"</A>.
The other two features are discussed in the three sections following
this brief summary.
<TABLE CELLPADDING="3">
<TR VALIGN="TOP"><TD><P><B><TT><STRONG>inboard modules</STRONG></TT>
</B></TD><TD><P>Are compiled into Data Explorer.
That is, the version of dxexec found (usually) in
/usr/local/dx/bin&#95;architecture is replaced
with your own copy (i.e., a copy
incorporating your module).
</TD></TR><TR VALIGN="TOP"><TD><P><B><TT><STRONG>outboard modules</STRONG></TT>
</B></TD><TD><P>Run as separate processes.
Linking an outboard module is quick, since it does not involve creating
an entire new version of dxexec (as the compilation of
inboard modules does).
Thus an outboard module is also easier to debug because it can be
relinked more quickly.
<P>
However, outboard modules are typically less efficient than other
modules, especially if significant amounts of data must be
transferred: data objects are transferred to and from an
outboard module via sockets rather than as the pointers
to shared memory that inboard and runtime-loadable
modules use.
</TD></TR><TR VALIGN="TOP"><TD><P><B><TT><STRONG>runtime-loadable
modules</STRONG></TT>
</B></TD><TD><P>Can be loaded when Data Explorer is started or at any time
after, and they
do not require a separate copy of dxexec, as inboard modules do.
Thus these modules have the advantage of portability without the
disadvantage of the data-transfer overhead associated with
outboard modules.
A single executable can contain multiple modules that can be used
like a library.
</TD></TR></TABLE>
<P><HR><B>&#91; <A HREF="#Top_Of_Page">Top of Page</A> &#124; <A
HREF="progu038.htm">Previous Page</A> &#124; <A HREF="progu040.htm">Next
Page</A> &#124; <A HREF="../proguide.htm#ToC">Table of Contents</A> &#124; <A
HREF="progu037.htm#PToC13">Partial Table of Contents</A> &#124; <A
HREF="progu344.htm#HDRINDEX_START">Index</A> &#93;</B> <br><b>&#91;<a
href="../allguide.htm">Data Explorer Documentation</a>&nbsp;&#124;&nbsp;<a
href="../qikguide.htm">QuickStart Guide</a>&nbsp;&#124;&nbsp;<a
href="../usrguide.htm">User&#39;s Guide</a>&nbsp;&#124;&nbsp;<a
href="../refguide.htm">User&#39;s Reference</a>&nbsp;&#124;&nbsp;<a
href="../proguide.htm">Programmer&#39;s Reference</a>&nbsp;&#124;&nbsp;<a
href="../insguide.htm">Installation and Configuration
Guide</a>&nbsp;&#93;</b><br><p><b>&#91;<a
href="http://www.research.ibm.com/dx">Data Explorer Home
Page</a>&#93;</b><p><HR ALIGN=LEFT WIDTH=600><b>&#91;<A
HREF="http://www.ibm.com/">IBM Home Page</A>&nbsp;&#124;&nbsp;<A
HREF="http://www.ibm.com/Orders/">Order</A>&nbsp;&#124;&nbsp;<A
HREF="http://www.ibm.com/Search/">Search</A>&nbsp;&#124;&nbsp;<A
HREF="http://www.ibm.com/Assist/">Contact IBM</A>&nbsp;&#124;&nbsp;<A
HREF="http://www.ibm.com/Legal/">Legal</A>&nbsp;&#93;</b><hr><p>
<A NAME="Bot_Of_Page"></A>
</BODY></HTML>
